US Defense Secretary Jim Mattis visited the heavily militarized border dividing the Korean peninsula with South Korean counterpart, Song Young-moo, on Friday.

Mattis arrived in South Korea earlier in the day for a two-day trip to the country for annual defense talks.

Mattis said the US goal was not to wage war with Pyongyang but to convince leader Kim Jong Un to give up his nuclear arsenal. He emphasized diplomatic efforts to find a peaceful solution to the crisis during his week-long trip to Asia, even as North Korea's weapons tests and bellicose verbal exchanges between Pyongyang and Washington stoke fears of an armed confrontation.

US intelligence experts say Pyongyang believes it needs the weapons to ensure its survival and have been skeptical about diplomatic efforts, focusing on sanctions, to get Pyongyang to denuclearize. The United States on Thursday imposed sanctions on seven North Korean individuals and three entities for "flagrant" human rights abuses, including killings, torture, forced labor and the hunting down of asylum seekers abroad.